The Hair Growth Cycle
It should be explained that in most mammals, hair does not grow continuously, but undergoes a cycle of activity involving alternate periods of growth and rest. The hair growth cycle can be divided into three main stages, namely:
(i) an active stage known as anagen, during which the hair follicle penetrates deep into the dermis with the cells of the bulb dividing rapidly and differentiating to form the hair, PA1 (ii) a regressive stage known as catagen, which is heralded by the cessation of mitosis, and during which the follicle regresses upwards through the dermis and hair growth ceases, PA1 (iii) a resting stage known as telogen, in which the regressed follicle contains a small secondary germ with an underlying ball of tightly packed dermal papilla cells. PA1 X.sup.2 is chosen from an alkyl or hydroxyalkyl group having from 1 to 18 carbon atoms; PA1 Y.sup.1, Y.sup.2, Y.sup.3 and Y.sup.4 are each chosen from H, an alkyl group having from 1 to 12 carbon atoms, and an acyl group having from 1 to 18 carbon atoms; PA1 l is an integer of from 1 to 3; PA1 m and n are each 0 or the integer 1 or 2; and PA1 m+n is 1 or 2. PA1 Allosaccharic acid PA1 Altrosaccharic acid PA1 Glucosaccharic acid PA1 Mannosaccharic acid PA1 Gulosaccharic acid PA1 Idosaccharic acid PA1 Galactosaccharic acid, and PA1 Talosaccharic acid. PA1 Benzalkonium chloride PA1 Benzethonium chloride PA1 Phenol PA1 Estradiol PA1 Diphenhydramine hydrochloride PA1 Chlorpheniramine maleate PA1 Chlorophyllin derivatives PA1 Cholesterol PA1 Salicylic acid PA1 Methionine PA1 Cystine PA1 Red pepper tincture PA1 Benzyl nicotinate PA1 dl-Menthol PA1 Peppermint oil PA1 Calcium pantothenate PA1 Panthenol PA1 Castor oil PA1 Hinokitiol PA1 Prednisolone PA1 Resorcinol PA1 M represents --H or SO.sub.3 M.sub.1, where M.sub.1 is an organic or metallic cation, particularly an alkali metal; or an acetyl group; PA1 R represents a C.sub.1 to C.sub.4 alkyl radical, especially methyl; or an aryl radical; PA1 or --COOR.sub.1, where R.sub.1 represents --H or a C.sub.1 to C.sub.4 alkyl radical, especially methyl; or a metal, especially an alkali metal; PA1 esterified oligosaccharides as described by Unilever in EP-A-0 211 610, including at least one esterified disaccharide unit consisting of a uronic acid residue having the structure (4a): ##STR4## and a hexosamine residue having the structure: (5) ##STR5## where R' is --H, C.sub.3 to C.sub.10 alkyl or ##STR6## R" is --H, C.sub.1 to C.sub.4 alkyl, --CO(CH.sub.2).sub.m CH.sub.3, --SO.sub.3 M, PA1 R'" is --H, --CO(CH.sub.2).sub.m CH.sub.3, or --SO.sub.3 M, PA1 M is --H, or a metallic or organic cation PA1 n is 0 or an integer of from 1 to 7, and PA1 m is 0 or the integer 1 or 2; PA1 iii. Minoxidil and certain derivatives thereof as described by the Upjohn Co. in U.S. Pat. No. 3,461,461, PA1 iv. Minoxidil glucuronides, as described by Unilever in EP-0 242 967, PA1 v. Minoxidil sulphates, as described by The Upjohn Co. in WO 86/04231, PA1 vi. Ethylenediaminetetraacetic acid or salts thereof, as described by Redken Laboratories, Inc. in U.S. Pat. No. 4,814,351. PA1 vii. Aldonolactones, such as D-glucaro-1,4-lactone, as described by Unilever in EP-0 277 428. PA1 viii. Direct proteoglycanase inhibitors, such as 1,10-phenanthroline, as described by Unilever in EP-0 277 428. PA1 ix. Glycosaminoglycanase inhibitors, as described by Unilever in EP-0 277 428, such as aldonolactones and esterified aldonolactones having the structure (5): ##STR7## where A.sup.1 and A.sup.2 are --H, ##STR8## B is OD" or a lactone linkage to position 1 or 6, or --NHCOCH.sub.3 and where D is --H or C.sub.2 to C.sub.8 alkyl, PA1 L-Galactono-1,4-lactone PA1 L-Arabino-1,5-lactone PA1 D-Fucono-1,5-lactone PA1 D-Glucaro-1,4-lactone PA1 D-Glucurono-6,3-lactone PA1 Galactaric acid lactone PA1 2-Acetamido-2-deoxygluconolactone PA1 2-Acetamido-2-deoxygalactono-lactone PA1 D-Glucaro-1,4:6,3-dilactone PA1 L-Idaro-1,4-lactone PA1 2,3,5-Tri-0-acetyl-D-glucaro-1,4-lactone PA1 2,5-Di-0-acetyl-D-glucaro-1,4:6,3-dilactone. PA1 G is --H, --SO.sub.3 M", C.sub.2 (ie acetyl) to C.sub.4 acyl PA1 G' is --H or --OG PA1 M" is --H or a metal cation PA1 N-Acetylglucosamine PA1 N-Acetylgalactosamine PA1 D-Galactosamine PA1 D-Glucosamine-3-sulphate PA1 N-Acetylmannosamine. PA1 D is --H or C.sub.2 to C.sub.8 alkyl PA1 M" is --H or a metal cation; PA1 the Q groups being the same or different, and at least one of which is involved in a lactam linkage; PA1 and where T is the same or different and is chosen from PA1 provided that: PA1 where any of the Q groups is PA1 D-glucaro-1,5-lactam L-Galactono-1,4-lactam, PA1 L-Arabino-1,5-lactam, D-Fucono-1,5-lactam, PA1 D-Glucaro-1,4-lactam, D-Glucurono-6,3-lactam, PA1 1,2,5-tri-0-acetyl-D-glucurono-6,3-lactam PA1 2-Acetamido-2-deoxygluconolactam, PA1 2-Acetamido-2-deoxygalactonolactam, PA1 D-Glucaro-1,4:6,3-dilactam, L-Idaro-1,4-lactam, PA1 2,3,5-Tri-0-acetyl-D-glucaro-1,4-lactam, PA1 2,5-Di-0-acetyl-D-Glucaro-1,4:6,3-dilactam, PA1 D-glucaro-1,5-lactam ethyl ester; PA1 the X and X' groups being of either stereochemical configuration with respect to the carbon backbone of the glycerol molecule; PA1 1,2-Dibutanoyl-rac-glycerol PA1 1,2-Dihexanoyl-sn-glycerol PA1 1,2-Dioctanoyl-rac-glycerol PA1 1,2-Dioctanoyl-sn-glycerol PA1 1,2-Didecanoyl-rac-glycerol PA1 1-Oleoyl-2-acetyl-rac-glycerol PA1 1-Oleoyl-2-acetyl-sn-glycerol PA1 1-Stearoyl-2-arachidonoyl-sn-glycerol PA1 1,2-Distearoyl-rac-glycerol PA1 1,2-Dipentadecanoyl-sn-glycerol PA1 1,2-dipentadecanoyl-rac-glycerol PA1 1,2-Dipalmitoyl-rac-glycerol PA1 1,2-Dipalmitoyl-sn-glycerol PA1 1,2-Diseptadecanoyl-rac-glycerol PA1 1,2-Dioleoyl-sn-glycerol PA1 1,2-Dioleoyl-rac-glycerol PA1 1,2-Diarachidonoyl-sn-glycerol PA1 1,2-Dieicosanoyl-sn-glycerol PA1 1,2-Didoeicosanoyl-rac-glycerol, and PA1 1,2-Dioctaeoicosanoyl-sn-glycerol. PA1 said substituents B being the same or different, and being in either configuration, with respect to the backbone of the above structure, on positions C.sup.2 to C.sup.5 not involved in a lactone ring; PA1 and where R.sup.4 is --H, C.sub.1 to C.sub.20 alkyl, a metal cation, NH.sub.4 + or an alkanolamine cation; PA1 provided also that, when A.sup.5 is ##STR21## and all B.sup.1, B.sup.2, B.sup.3 and B.sup.4 substituents are --OH, then A.sup.6 is ##STR22## or CH.sub.2 OR.sup.6, and R.sup.4 is C.sub.1 or C.sub.9 to C.sub.20 alkyl; PA1 6-acetyl-galactono-1,4-lactone PA1 6-propionyl-galactono-1,4-lactone PA1 6-butyryl-galactono-1,4-lactone PA1 2-propionamido-2-deoxygluconolactone PA1 2-butyramido-2-deoxygluconolactone PA1 2-propionamido-2-deoxygalactonolactone PA1 2-butyramido-2-deoxygalactonolactone PA1 6-propionyl-2-acetamido-2-deoxygluconolactone diacetyl-6-propionyl-2-acetamido-2-deoxygluconolactone PA1 6-butyryl-2-acetamido-2-deoxygalactonolactone diacetyl-6-butyryl-2-acetamido-2-deoxygalactonolactone PA1 2,3,5,6-tetraacetyl-galactono-1,4-lactone PA1 2,3,5-triacetyl-6-propionylgalactono-1,4-lactone PA1 triacetyl-2-propionamido-2-deoxygalactonolactone PA1 triacetyl-2-butyramido-2-deoxygluconolactone PA1 6-methyl-glucaro-1,4-lactone PA1 2,3,5,6-tetramethyl-glucaro-1,4-lactone PA1 6-methyl-2,3,5-triacetylglucaro-1,4-lactone PA1 6-methyl-3-methyl-glucaro-1,4-lactone, and PA1 6-methyl-3-acetyl-glucaro-1,4-lactone; PA1 1,2,5-triacetyl-glucurono-6,3-lactone. PA1 D.sup.1 is ##STR24## where X.sup.2 is an ether linkage either to C.sup.4 or C.sup.5 forming a pyranose or furanose ring; PA1 Y is --H, --SO.sub.3 M, C.sub.2 to C.sub.4 acyl or C.sub.1 to C.sub.18 alkyl; PA1 said substituents A.sup.7, B.sup.5, B.sup.6 and --OY being the same or different, and being in either configuration, with respect to backbone of the above structure; PA1 and where Z.sup.1 is --H or --OY PA1 R.sup.8 is --H, --SO.sub.3 M.sup.2 or C.sub.3 or C.sub.4 acyl, PA1 M.sup.2 is --H, a metal cation, NH.sub.4 +, or PA1 an alkanolamine cation; PA1 2-propionamido-2-deoxyglucose PA1 1,3,4,6-tetraacetyl-2-propionamido-2-deoxyglucose PA1 2-butyramido-2-deoxygalactose PA1 1,3,4,6-tetraacetyl-2-butyramido-2-deoxygalactose PA1 2-sulphamido-2-deoxygalactose PA1 2-sulphamido-2-deoxyglucose PA1 2-butyramido-2-deoxymannose PA1 1,3,4,6-tetraacetyl-2-butyramido-2-deoxyglucose PA1 2-butyramido-2-deoxyglucose, and PA1 1,3,4,6-tetraacetyl-2-butyramido-2-deoxyglucose. PA1 v is zero, or the integer 1 or 2, PA1 w is zero, or an integer of from 1 to 21 PA1 x is zero, or an integer of from 1 to 4, PA1 y is zero, or the integer 1 or 2, PA1 z is zero, or an integer of from 1 to 4, and PA1 u+v+w+x+y+z is an integer of from 1 to 22; PA1 pyroglutamic acid methyl ester PA1 pyroglutamic acid ethyl ester PA1 pyroglutamic acid n-propyl ester PA1 pyroglutamic acid n-butyl ester PA1 pyroglutamic acid n-hexyl ester PA1 pyroglutamic acid n-heptyl ester PA1 pyroglutamic acid n-octyl ester PA1 pyroglutamic acid n-nonyl ester PA1 pyroglutamic acid n-decyl ester PA1 pyroglutamic acid n-undecyl ester PA1 pyroglutamic acid n-dodecyl ester PA1 pyroglutamic acid n-tridecyl ester PA1 pyroglutamic acid n-tetradcyl ester PA1 pyroglutamic acid n-hexadecyl ester PA1 pyroglutamic acid n-octadecyl ester PA1 pyroglutamic acid n-eicosyl ester PA1 pyroglutamic acid iso-propyl ester PA1 pyroglutamic acid 2-methylhexyl ester PA1 pyroglutamic acid 2-ethylhexyl ester PA1 pyroglutamic acid 3,7-dimethyloctyl ester PA1 pyroglutamic acid 2-hexyldecyl ester PA1 pyroglutamic acid 2-octyldodecyl ester PA1 pyroglutamic acid 2,4,4-trimetyl-1-pentane ester PA1 pyroglutamic acid methyloctyl ester PA1 methyl PA1 ethyl PA1 propyl PA1 iso-propyl PA1 butyl PA1 iso-butyl PA1 n-valeryl PA1 iso-valeryl PA1 n-caproyl PA1 n-heptyl PA1 n-caprylyl PA1 n-capryl PA1 lauryl PA1 myristyl PA1 palmityl PA1 stearyl, and PA1 arachidyl. PA1 linoleyl PA1 linolenyl PA1 .alpha.-linolenyl PA1 arachidonyl, and PA1 columbinyl. PA1 hydroxymethyl PA1 2-hydroxyethyl PA1 2-hydroxy-n-propyl PA1 3-hydroxy-n-propyl PA1 2-hydroxy-n-butyl PA1 3-hydroxy-n-butyl PA1 4-hydroxy-n-butyl PA1 5-hydroxy-n-valeryl PA1 6-hydroxy-n-caproyl PA1 2,3-dihydroxy-n-propyl PA1 2,3-dihydroxy-n-butyl PA1 12-hydroxystearyl. PA1 2-[pyroglutamoyloxy]-propionic acid PA1 methyl-2-[pyroglutamoyloxy]-acetate PA1 ethyl-2-[pyroglutamoyloxy]-n-propionate PA1 ethyl-2-[pyroglutamoyloxy]-n-butyrate PA1 ethyl-2-[pyroglutamoyloxy]-iso-butyrate PA1 ethyl-2-[pyroglutamoyloxy]-n-valerate PA1 ethyl-2-[pyroglutamoyloxy]-n-caproate PA1 ethyl-2-[pyroglutamoyloxy]-n-heptylate PA1 ethyl-2-[pyroglutamoyloxy]-n-caprylate PA1 ethyl-2-[pyroglutamoyloxy]-n-pelargonate PA1 ethyl-2-[pyroglutamoyloxy]-3-hydroxybutyrate PA1 iso-propyl-2-[pyroglutamoyloxy]-n-propionate PA1 iso-propyl-2-[pyroglutamoyloxy]-n-caprylate PA1 n-propyl-2-[pyroglutamoyloxy]-n-propionate PA1 n-propyl-2-[pyroglutamoyloxy]-n-caprylate PA1 stearyl-2-[pyroglutamoyloxy]-n-propionate PA1 12-hydroxystearyl-2-[pyroglutamoyloxy]-n-propionate PA1 stearyl-2-[pyroglutamoyloxy]-n-stearate PA1 palmityl-2-[pyroglutamoyloxy]-n-propionate PA1 linoleyl-2-[pyroglutamoyloxy]-n-propionate PA1 linoleyl-2-[pyroglutamoyloxy]-n-caprylate PA1 lauryl-2-[pyroglutamoyloxy]-n-caprylate PA1 stearyl-2-[pyroglutamoyloxy]-n-caprylate PA1 glyceryl mono(2-[pyroglutamoyloxy]-n-propionate) PA1 glyceryl mono(2-[pyroglutamoyloxy]-n-caprylate), and PA1 glyceryl di(2-[pyroglutamoyloxy]-n-propionate). PA1 2-methyl propan-2-ol PA1 Propan-2-ol PA1 Ethyl-2-hydroxypropanoate PA1 Hexan-2,5-diol PA1 POE(2) ethyl ether PA1 Di(2-hydroxypropyl) ether PA1 Pentan-2,4-diol PA1 Acetone PA1 POE(2) methyl ether PA1 2-hydroxypropionic acid PA1 2-hydroxyoctanoic acid PA1 Propan-1-ol PA1 1,4 Dioxane PA1 Tetrahydrofuran PA1 Butan-1,4-diol PA1 Propylene glycol dipelargonate PA1 Polyoxypropylene 15 stearyl ether PA1 Octyl alcohol PA1 POE ester of oleyl alcohol PA1 Oleyl alcohol PA1 Lauryl alcohol PA1 Dioctyl adipate PA1 Dicapryl adipate PA1 Diisopropyl adipate PA1 Diisopropyl sebacate PA1 Dibutyl sebacate PA1 Diethyl sebacate PA1 Dimethyl sebacate PA1 Dioctyl sebacate PA1 Dibutyl suberate PA1 Dioctyl azelate PA1 Debenzyl sebacate PA1 Dibutyl phthalate PA1 Dibutyl azelate PA1 Ethyl myristate PA1 Dimethyl azelate PA1 Butyl myristate PA1 Dibutyl succinate PA1 Didecyl phthalate PA1 Decyl oleate PA1 Ethyl caproate PA1 Ethyl salicylate PA1 Isopropyl palmitate PA1 Ethyl laurate PA1 2-ethyl-hexyl pelargonate PA1 Isopropyl isostearate PA1 Butyl laurate PA1 Benzyl benzoate PA1 Butyl benzoate PA1 Hexyl laurate PA1 Ethyl caprate PA1 Ethyl caprylate PA1 Butyl stearate PA1 Benzyl salicylate PA1 2-hydroxypropanoic acid PA1 2-hyroxyoctanoic acid, PA1 Dimethyl sulphoxide PA1 N,N-Dimethyl acetamide PA1 N,N-Dimethyl formamide PA1 2-Pyrrolidone PA1 1-Methyl-2-pyrrolidone PA1 5-Methyl-2-pyrrolidone PA1 1,5-Dimethyl-2-pyrrolidone PA1 1-Ethyl-2-pyrrolidone PA1 Phosphine oxides PA1 Sugar esters PA1 Tetrahydrofurfural alcohol PA1 Urea PA1 Diethyl-m-toluamide, and PA1 1-Dodecylazacyloheptan-2-one PA1 (i) Anionic surface active agents, such as metallic or alkanolamine salts of fatty acids for example sodium laurate and triethanolamine oleate; PA1 (ii) Cationic surface active agents, such as amine salts, for example sapamin hydrochloride; PA1 (iii) Amphoteric suface active agents, such as imidazol compounds, for example Miranol; PA1 betaines, for example cocoamidopropylbetaine PA1 (iv) Nonionic surface active agents, such as fatty acid alkanolamides, for example oleic ethanolamide; PA1 (c) cationic polymer chosen from; PA1 Guar Hydroxypropyltrimonium chloride PA1 Quaternium-19 PA1 Quaternium-23 PA1 Quaternium-40 PA1 Quaternium-57 PA1 Poly(dipropyldiallylammonium chloride) PA1 Poly(methyl-.beta.-propaniodiallylammonium chloride) PA1 Poly(diallylpiperidinium chloride PA1 Poly(vinyl pyridinium chloride) PA1 Quarternised poly (vinyl alcohol) PA1 Quarternised poly (dimethylaminoethylmethacrylate); and PA1 mixtures thereof
The initiation of a new anagen stage is revealed by rapid proliferation in the germ, expansion of the dermal papilla and elaboration of basement membrane components. The hair cycle is then repeated many times until, as a consequence of the onset of male pattern baldness, most of the hair follicles spend an increasing proportion of their time in the telogen stage, and the hairs produced become finer, shorter, and less visible; this is known as terminal to vellus transformation.